-LRB- CNN -RRB- -- The American leg of Miley Cyrus ' tour is now officially over , thanks to an `` extreme allergic reaction '' to an antibiotic .

Her representative released a statement Friday indicating that `` all remaining U.S. dates on the Miley Cyrus ` Bangerz ' tour have been postponed . '' That means that shows scheduled next week for Philadelphia , at Foxwoods casino in Connecticut , and on Long Island , New York are officially off -- at least for now .

The announcement is n't entirely unexpected : Her representative said Thursday that the entertainer could need a lot more time to recover from the ailment that landed her in a Kansas City hospital last week .

`` Sick of waking up to needles , '' the 21-year-old Cyrus tweeted Friday . '' #goingthruit . ''

The singer canceled a show in Charlotte , North Carolina , last week because of what was reported to be a flu-like illness . But the severity of her condition was n't fully known until this week , when she canceled performances in Kansas City and St. Louis .

In a statement , her camp explained that Cyrus got a sinus infection while in North Carolina , then `` was prescribed the antibiotic Cephalexin , which she has now suffered an extreme allergic reaction to . ''

`` This type of extreme reaction can last from five to 27 days in these types of cases , '' the statement said .

`` She will remain hospitalized and is under a doctor 's care until we see some improvement in her condition and is asking for your compassion and privacy at this time . Miley is devastated about missing shows and possibly disappointing her fans . ''

But it appears Cyrus wo n't be off the stage for long .

Her representative said Friday `` the European leg of the tour will proceed as planned , '' starting with a May 2 date in Amsterdam .

This summer , she should be back partying in the USA , as she intoned in one of her best-known hits .

A slew of new shows , running between August 1 and August 14 , were announced Friday to replace recently canceled ones . Those dates include two additional shows in Pittsburgh and Chicago .

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CNN 's Carolyn Sung and Alan Duke contributed to this report .

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The remaining U.S. dates on Cyrus ' `` Bangerz '' tour are called off -- for now

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The European leg of her tour , set to start May 2 , is still on , her camp says

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Cyrus has been hospitalized because of an allergic reaction to an antibiotic

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`` Sick of waking up to needles , '' the 21-year-old singer tweets